In an internal combustion engine, fuel and an oxidizing agent, such as air, undergo combustion in a combustion chamber. The resulting expansion of high pressure and high temperature gases applies a force to a movable component of the engine, such as a piston causing it to move, thereby, resulting in mechanical energy.
Internal combustion engines are used in a wide variety of applications, including, for example, automobiles, motorcycles, ship propulsion and generation of electricity.
It is generally desirable for internal combustion engines to be compact and highly efficient.